Basic, Easy, and Free Campsite with Bouldering Nearby
Oak Flat is a Forest Service campground in the Tonto National Forest and is about 90 minutes from Phoenix. It's a short distance off a windy mountain highway which means it's easy to get to but traffic can be heard from camp. (Luckily it's not a busy interstate and traffic is pretty infrequent at night.) It's not spectacular location but there are decent views of the oak scrub desert surrounding the camp.
There are a handful of campsites with picnic tables and firepits, plus several flat and open areas for RVs or tent cities. Some sites are open and others have a few shady tree for hammocks, slacklines, and more. There is a bathroom which was clean and well-stocked with toilet paper, despite the campground being quite full when I stayed here for a few nights in April. There is no water, however, so be prepared with as much as you'll need. The elevation is just shy of 4,000' which means nights are typically a few degrees cooler than in the Phoenix area.
There are no hiking trails from the campground but there is a network of dirt roads which take you back into the desert scrub oak forest and through hundreds of bouldering problems of all levels. Just a few miles away, however, the Arizona Trail crosses the highway and heads north into the Superstition Wilderness.
This campsite is pretty basic but is a good place to kill some time, especially given that it's free! It's also a great place to set up your base camp if you want to do some bouldering.